Flexible mandrel



May 3, 1932- A. E, sTJARNsTRoM 1,856,597

FLEXI BLE MANDREL Filed June 9, 1931 SWW/nto@ HZZSi/'arnslrom Patented May 3, 1932 PATENT OFFICE ARTHUR E. STJARNSTROM, OF CLEVELAND, OHIO FLEXIBLE MANDREL Application filed `Tune 9, 1931.

This invention relates to mandrels, and more particularly to mandrels of the flexible t e.

ypAn object of this invention is to provide a 6 mandrel of this kind which may be readily positioned in a tubular member so as to prevent kinking of the tube during the bending thereof.

Another object of this invention is to pro- 10. vide a flexible shaft withV means for maintaining the shaft in a central position within a tubular support.

Another object of this invention is to provide in a device of this kind means by which the device may be disposed at turns in a tubular conductor or the like, for holding the conductor in its original round form during the bending of the conductor so as to eliminate the necessity of filling the conductor or tube with a filling element in the form of sand,

lead, or the like. Y

A further obj ect of this invention is to provide in a device of this kind means by which the component parts thereof may be readily tightened so that they will not separate during the bending of the member within which they are disposed.

A still further object of this invention is to provide a flexible shaft which is held concentrically of the tubular support by members disposed about the shaft, these members being capable of relative movement one with respect to the other, so that the shaft may be bent and maintained in bent form while simultaneously being held concentrically of the tubular support.

The above and various other objects and advantages of this invention will in part be described in and in part be understood from the following detailed description of the present preferred embodiment, the same being illustrated in the accompanying drawings, wherein Y Figure 1 is a fragmentary detail side elevation of a device constructed according to the preferred embodiment of this invention; Figure 2 is a longitudinal section taken substantially through the center of the device;

Serial No. 543,185.

Figure 3 is a detail end elevation of the device;

Figure 4 is a sectional view taken substantially through the longitudinal center of one of the end members, and

Figure 5 is a sectional View taken through the center of one of the intermediate joint members.

Referring to the drawings wherein like numerals of reference designate corresponding parts throughout the several views, the numeral 10 designates generally a flexible shaft or cable of desired length, which is provided at one end with a substantially spherical member 11 which is provided with a bore 13 therethrough within which one end of the cable of shaft 10 is secured as by soldering, welding or the like.

The opposite end of the cable or shaft 10 has a plug 12 secured thereto, which plug 12 is threadably mounted in a nut member 14, and this plug 12 is held against rotation within the nut 14 by means of a pin 15, which extends through the nut 14 and the plug 12. The plug 12 is also provided at the outer end thereof with a slot 16 disposed diametrically therethrough, which is adapted to be engaged by a screw driver or the like, for rotating the plug 12 within the nut 14.

A plurality of segmental members 17 having a tapering bore 18 therethrough are provided with a concave face portion 19 and a convex portion 20. This concave portion 19 is adapted to engage the convex surface of the spherical member 11, and the concave surface of the member 17 is adapted to be engaged by the convex surface 19 of another segmental member 17. In this manner, any number desired of these convex members or joints 17 may be provided, depending upon the length of the curve which it is desired to make in th-e tubular member.

An inner end member 21 engages the last of the joint members 17, this member 21 having a bore 22`therethrough for loosely engaging about the cable 10, and this end member 21 is adapted to have the convex surface 23 thereof engaged by the outer end of the nut member 14. VThrough the provision of a nut member 14 having a threaded bore 24 therein, any desired number of cables may be joined together, so that where the cable or shaft 10 is used as a flexible shaft which rotates within the joint members 17, the desired length of the shaft may be readily accomplished by connecting a number of the nut members 14 and plug members 12 together.

Y Through the provision of the tapering apert'ureA 0r bore 18 in the point members 17 ,the

shaft or cable 10 may be readily bent or flexed Within the various joint members.

In the use of this device, the spherical member 11 and the ,joint members 17 are construc'ted of a diameter substantially*v equal to the inner diameter of a pipe or conduit which it is desired to' bend, or within. which the shaft 10 is to be positioned, and whenvthe de- -sired number ofjont members 17 have been mounted on the shaft 10, thel nut1/1 may be threadably disposed about the plug-12 and the pin 15 passed therethrough so as to securely hold the plug L12 vagainst rotation with respect to the nut 14 and to hold the joint and having a threaded bore within which said i plug is disposed, one end of said nut engag ing oneof said joint .members whereby to force said one joint member inwardly of the adjacent end of the flexible member, and means for holding said nut against rotation with respect to said plug. r

.o 2. A mandrel of the character described comprising an elongated flexible member adapted to be disposed in a tubular suppoi t, a spherical member secured to one end of said flexible member, a plurality of intermediate joint members disposed about said flexible member and engaging the inner surfaceof Ysaid tubular support, said flexible member having rotary movement withl respect to said j of'nt members, said joint members having tapering apertures loosely receiving said flexible member, and` threaded tightening means carried by the opposite end of 'f said flexible member whereby to hold,said joint members into contact with eachother. Y j

In testimony whereof I hereunto affix my signature. v Y Y. t

' ARTHUR E. STJARNSTROM.

that when the tube is bent, the bent portion e ofthe tube will not be `flattened or kinlred, but will maintain its round form, I do notk wish to be limited to this construction or use, as the cable 10 may also be used vas a flexible shaft, in which case these joint ymembers 17 will serve as bearings for the shaft 10'sothat when the shaft 10V is rotated within the bore 18 of each joint member 10, the shaft will Vbe maintained at all times concentrically within l thetubular support.

Itis, ofcourse, understood that vvarious changes and modifications may be made in the details of construction andldesign of the Yabove speciiicallyfdescribed embodiment of this` invention without departing from the Y spirit thereof, such changes and modifications being restricted only bythe scope of the following'claims.l j f I claimz'- n i 1. A mandrel lof the character described comprising an elongatedv flexible member adapted to-be disposedin a' pipe, a round vend member secured to one end ofnsaid vflexible member, intermediate concavo-convex joint v y members disposed intermediate the ends of said exible member,one of 'said joint members'engaging said round member,a threaded plug secured to the" opposite end of saidflexi'- -ble y'inen'ub/er, a nut 'disposed yabout said plufg 

